I have limited access to thread pictures from work, was able to see the 2 dyno sheets.
Is it correct to say that you got to 24 PSI by around 3900-4000 RPM?
Was this 4th gear with intake temperature over 70F?
There could be additional spool advantages with reversing the manifold, but that would complicate the turn-key side of this package and I know that reliabillity is a main goal with KB, so I think they made the right choice keeping it the way it is.
Personally, I'd like to see a smaller turbo with a quicker spool as an option here (something good for 320 WHP, fully spooled by 3300 RPM), but it's a nice option as it is.